Isoform‐specific shRNA‐mediated silencing of Nox5 impaired proliferation of PCa cell lines that express readily detectable levels of Nox5 (namely PC‐3 and LNCaP) but had only weak and non‐significant effect on DU145 cells, which express only very low levels of Nox5. Here, NOX5 is linked to posterior cortical atrophy.